Rosie, an 18-Month-Old in the Young Toddler Classroom, Is Cared

Rosie, an 18-month-old in the young toddler classroom, is cared for by two responsive caregivers. One caregiver is very expressive while the other is quiet and more reserved. Rosie's father has noticed that Rosie responds to the very big smiles of one caregiver, but also responds to the very subtle smiles of the other caregiver. This could be evidence of the child's

A) development of self-conscious emotions.
B) inability to manage the difference in the two caregiving styles.
C) temperament being mismatched with one of the caregivers.
D) ability to express multiple emotions.
E) ability to discriminate gradations in emotions.